The present invention relates generally to the keeping of live aquatic creatures for pleasure, relaxation or scientific study and to aquariums and more particularly to a rotating aquarium as intended to facilitate the keeping of such aquatic creatures.
The ocean, due to its great volume, is nutrient poor. In order for coral animals to survive in this nutrient poor environment, they evolved with zooxanthellae (tiny plants) that live inside them in a symbiotic relationship. Through photosynthesis, the zooxanthellae produce food for the host coral and they receive nitrogen, phosphorous and carbon dioxide in return. When corals do not receive enough light, the zooxanthellae can die and the coral will turn white or bleach as a result. This often leads to the death of the corals as well. Delbeek, J. Charles; Sprung, Julian; The Reef Aquarium, 1994 (Ricordea Publishing).
While the keeping of tropical fish is certainly not a new hobby, the successful captive maintenance of the living coral reefs is a very recent variation. The natural environment must be recreated as much as possible. A common problem associated with the keeping of corals, such as stony corals (species acropora), is coral bleaching. As described above, coral bleaching is partial depigmentation caused by the death of zooxanthellae from inadequate light. In nature, the earth rotates on its axis and revolves around the sun. The coral receives sunlight from many angles when the earth rotates about its axis. This exposure to sunlight, and particularly to sunlight at different angles, prevents coral bleaching.
Additionally, in the ocean, sedentary corals receive food and waste removal through the constant water movement from currents and wave action. This enables the coral to grow and prosper in the ocean setting.
In a conventional stationary aquarium with a fixed light source, corals can actually shade themselves as the upper branches block light from reaching the lower branches. Further, coral tend to grow toward the fixed light source in a conventional aquarium. Faster growing coral species can thus obscure the light source to slower growing coral species within the aquarium. This can cause non-uniform coral growth. Both of these phenomena, i.e. shading cause by the corals' own branches or shading caused by faster growing coral species, result in coral bleaching, where zooxanthellae die from inadequate light. Further, in the conventional aquarium, corals can literally smother from pollution from their own wastes in areas of inadequate water movement.
In conventional aquariums, water movement can be created using pumps. However, there are usually dead spots or at least areas with little water movements. Moreover, in attempting to create adequate water movement, multiple pumps are used. These pumps produce heat which results in increased temperatures and causes a problem in regulating the environment of the aquarium to the appropriate temperature. Finally, another disadvantage of conventional aquariums is that they are only viewed by the user from one angle. Even if the conventional aquarium is landscaped, or aquascaped, to provide different views, the user cannot appreciate the different views of the aquarium without moving from his or her vantage point. This is a particular disadvantage for a tank that includes corals.
What is needed, then, in the prior art is a rotating aquarium that can provide adequate lighting from many angles and can facilitate water transfer. Such an aquarium is lacking in the prior art. This needed system must also be capable of reversing direction manually or automatically through use of a timer.